444 Wisconsin Academy of Sciences, Arts and Letters. 
a little wider in front. Front eyes in a curved row, large, mid¬ 
dle less than twice lateral. Second row halfway between the 
others, or nearer the third, which is narrower than the cephalo¬ 
thorax. Clypeus high. Falces stout, vertical, with small fangs; 
lower margin with one small tooth. Sternum long, truncated 
in front. First coxae widely separated. Labium as wide as 
long. 
Ephippus americanus Keys, which Simon includes in Cory- 
thalia, belongs to the genus Pellenes. 
CORYTHALIA OPIMA P. 1885. 
1885. Jotus opimus P., Proc. Nat. Hist. Soc. Wis., p. 71. 
1888. Dynamius opimus E. S., Ann. Ent. Soc. Fr., p. 205. 
1893. Dynamitjs opimus P., Occ. Pap. Nat. Hist. Soc. Wis., Ill, 1, p. 12. 
1901. (Feb.). Sidusa fulvoguttata 5 F. O. P. C., Biol. Cent. Am., Aran. 
Arachn., II, p. 214. 
1901. (May). Corythalia opima E. S., Hist. Nat. des Araign., 2me 
Ed., II, p. 652. 
Length, 8 8 mm., 9 10.7 mm. Legs, 8 $ 3421, first three 
pairs enlarged and fringed, in the male. 
Spines, 8 , tib. I and II 3-3 and 3 anterior and 3 posterior 
lateral spines ; met. I and II 2-2 and 2 anterior and 2 pos¬ 
terior lateral spines; pat. I and II 1 anterior and 1 posterior 
spine. 
Coloration of 8 and $ . The cephalothorax is black; there is 
an indistinct patch of whitish hairs just above the middle an¬ 
terior eyes, and a smaller patch behind each of the eyes of the 
second row; a little way behind the dorsal eye, on each side, is 
a longitudinal band of white hairs which becomes narrower and 
somewhat curved as it passes backward. These bands are some¬ 
times united behind. It seems probable that the upper surface 
of the thoracic part was originally covered with white hairs, 
which have been more or less rubbed off in the different speci¬ 
mens. On the lower borders of the cephalothorax are bands of 
white hairs which begin opposite the dorsal eyes and run as far 
back as the part overlapped by the abdomen. The ground color 
